The "Back to the Future 2 Light Up Shoes" from HalloweenCostumes.com are officially licensed by Universal Studios and are therefore dead-ringers for Marty's kicks. Here's the movie version, should you need a reminder:

The costume shoes have the same high-topped grey leather, velcro "power laces," and LED lights in the soles (which can be charged with included power cord). All that's missing is that big ole Nike swoosh. And of course, the self-lacing technology.